1. Field of the Invention
The present invention relates to a inductive battery charger for inductive charging of a battery used on board in an electric vehicle.
2. Description of Related Art
As typically shown in FIG. 1, a inductive batter charger for an electric vehicle is provided with a magnetic coupler (primary side) 100 electrically connected to a converter and inverter (both not illustrated). On the other hand, the electric vehicle has provided inside a charge port 102 thereof a charge core 101 (secondary side) having a secondary coil 101A which is to be electrically connected to a battery (not illustrated) trough the converter and inverter. An electromagnetic induction with the secondary coil 101A of the primary-side magnetic coupler 100 induces a current in the secondary coil 101A to charge the battery on the electric vehicle.
However, the ordinary charge core (secondary side) 101 in the conventional inductive battery charger has the general shape of a simple rectangle or square as shown in FIG. 2, for example. It is thus unavoidable that a reduction of the width of the charge port 102 will result in a reduction of the sectional areas (S1+S2) of connections 103 (shown with hatching in FIG. 1) which link upper and lower members of the charge core 101. Therefore, the charging output (capability) will decrease correspondingly